Turkey has expressed concerns after a Kurd militant group with links to Kurdish militants in Turkey seized control of a Syrian border town after days of clashes with terrorist al Nusra fighters.

Turkey’s foreign minister voiced concern on Thursday at the spillover of violence from the Syria war which Ankara has been one of its great supporters.

Overnight fighting in the Syrian border town of Ras al-Ayn led to local Kurdish fighters ousting al-Qaeda-backed militants from the area.

Fighters from the Democratic Union Party (PYD) clashed with Jabhat al-Nusra fighters around the border area throughout the day Wednesday, with stray bullets crossing into Turkey and locals in the town of Ceylanpinar staying indoors as fighting raged in neighboring Syria.

The Turkish government’s reaction was harshly critical of the PYD, which it dubbed “separatist terrorists”.

The criticism comes as Turkish officials have been openly supporting al-Nusra to topple the government of Syrian president Bashar al-Assad, despite the group’s overt ties with al-Qaeda’s leadership.

Kurdish separatism has been a struggling problem for Turkey for a long time.

Analysts says Turkish government’s eagerness to back the anti-government militants in Syria was partly because they figured Arab nationalist rebels would crack down on Kurdish secessionist efforts more than Assad has already done.

Instead, Turkey has found itself allied with al-Qaeda and supporting a war that is leaving their southern border a destabilized mess.

Militants also blew up a section of a gas pipeline near Deir ez-Zor, which resulted in the loss of some 1.5 million cubic meters of natural gas.

The Syria crisis started in March 2011, when pro-reform protests turned into a massive insurgency following intervention of western and regional states.

The unrest, which took in terrorist groups from across Europe, the Middle East and North Africa, has transpired as one of the bloodiest conflicts in recent history.

As the foreign-backed insurgency in Syria continues without an end in sight, the US government boosts its political and military support to Takfiri extremists.

Washington has remained indifferent about warnings by Russia and other world powers about the consequences of arming militant groups.